Curable compositions containing a fluoroelastomer have excellent properties such as heat resistance, chemical resistance, solvent resistance, and fuel resistance, and are therefore widely used for production of molded products such as O-rings, hoses, valve stem seals, shaft seals, and diaphragms.
However, stricter demands have been placed on the properties of those various molded products as the technology has progressed; that is, molded products are desired which have higher properties than those obtained by conventionally employed peroxide cross-linking or polyol cross-linking.
In view of such a state of the art, curable compositions cross-linkable by triazine cross-linking have been proposed. For example, Patent Document 1 discloses a fluoroelastomer composition obtained by blending an organic acid ammonium salt or inorganic acid ammonium salt as a curing agent with a ternary copolymer of tetrafluoroethylene, perfluoro(lower alkyl vinyl ether) or perfluoro(lower alkoxy-lower alkyl vinyl ether), and a cyano group-containing perfluoro vinyl ether.
Patent Document 2 discloses a curable composition including a perfluoroelastomer of tetrafluoroethylene, a specific perfluoro vinyl ether, and a cure site monomer, and a compound that is other than an organic acid ammonium salt or an inorganic acid ammonium salt and produces ammonia when decomposed at 40° C. to 330° C.
Patent Document 3 discloses a curable composition that includes a fluoroelastomer containing a cyano group in a main chain and/or a side chain thereof and inorganic nitride particles, and the amount of the inorganic nitride particles is 0.1 to 20 parts by weight for each 100 parts by weight of the fluoroelastomer.
Patent Document 1: JP 9-111081 A
Patent Document 2: WO 00/09603 A
Patent Document 3: WO 2007/013397 A